Conventionally, various power storage devices are known such as electric double layer capacitors and secondary batteries. An example thereof is described in, for example, Patent Document 1. The power storage device described in Patent Document 1 includes: a first internal electrode extracted to a first end surface; a second internal electrode extracted to a second end surface; and a separator placed between the first internal electrode and the second internal electrode. On the first end surface, a first external electrode is placed which is electrically connected to the first internal electrode. On the second end surface, a second external electrode is placed which is electrically connected to the second internal electrode.    Patent Document 1: Japanese Patent Application Laid-Open No. 2012-33907